Mr Olugbenga Oyewole, the Senior Special Assistant to the President on Maritime Services, says the Federal Government has not concessioned maritime security to a private firm.
Oyewole, who spoke to journalists on Monday in Ibadan, said the rumour was being peddled by some elements in the maritime sector.
He explained that it was the statutory duty of the Navy in collaboration with the Nigerian Maritime Administration and Safety Agency (NIMASA)) to secure the nation's coastal waters.
Oyewole said it would be wrong to usurp the functions of the relevant institutions concerned with the task of securing the nation's water ways.
The presidential aide also said government was determined to deliver a sustainable maritime security programme.
Oyewole, who disclosed that some illegal activities were taking place on the nation's water ways, stressed the need to ensure the security of lives and property off-shore.
Government, he added, only engaged a private firm to supply patrol boats and surveillance equipment.
"NIMASA and the Navy will use these facilities to protect the maritime domain.
"This arrangement is aimed at reducing freight costs to Nigeria which, currently, is at war risk premium," Oyewole said.
The maritime initiative, he said, was to monitor offshore operations and accruable revenue as well as check importation of contraband goods.